The present invention is directed generally to surge detectors, and more particularly to a clamp-on surge detector for lightning arrestors which utilizes the distributed inductance of the ground return line of the arrestor to detect surge current.
In electrical power distribution systems it is frequently desirable to know if a discharge has occurred in a particular lightning arrester, since such discharges, if frequent, may damage the arrestor or related power system components.
In the past discharges in lightning arrestors have been detected by means of a varistor serially installed on the ground return lead of the arrestor. Since such varistors were relatively expressive and introduced an increased impedance in the ground return line, and required that the ground return line be disconnected for installation and removal, their use as surge detection elements was not entirely satisfactory. The present invention provides an economical self-powered surge detector which can be installed on the ground return lead of a lightning arrestor without disconnecting the lead, and which does not utilize a current transformer.
Accordingly, it is a general object of the present invention to provide a new and improved surge detector.
It is a more specific object of the present invention to provide a surge detector which is economical to construct and which does not require that the ground return conductor of a lightning arrestor be disconnected during installation of the detector.
It is a further object of the present invention to provide a self-powered surge detector which provides an output indicative of the number of surges which have occurred in a monitored conductor.